621 lines
37 KiB
HTML
621 lines
37 KiB
HTML
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<html lang="en"><head><META http-equiv="Content-Type" content="text/html; charset=UTF-8"><link href="../images/docs-stylesheet.css" rel="stylesheet" type="text/css"><title>Apache Tomcat 8 Configuration Reference (8.0.53) - The Host Container</title><meta name="author" content="Craig R. McClanahan"><meta name="author" content="Remy Maucherat"><meta name="author" content="Yoav Shapira"><script type="application/javascript" data-comments-identifier="tomcat-8.0-doc/config/host">
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</script></head><body><div id="wrapper"><header><div id="header"><div><div><div class="logo noPrint"><a href="https://tomcat.apache.org/"><img alt="Tomcat Home" src="../images/tomcat.png"></a></div><div style="height: 1px;"></div><div class="asfLogo noPrint"><a href="https://www.apache.org/" target="_blank"><img src="../images/asf-logo.svg" alt="The Apache Software Foundation" style="width: 266px; height: 83px;"></a></div><h1>Apache Tomcat 8 Configuration Reference</h1><div class="versionInfo">
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Version 8.0.53,
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<time datetime="2018-06-29">Jun 29 2018</time></div><div style="height: 1px;"></div><div style="clear: left;"></div></div></div></div></header><div id="middle"><div><div id="mainLeft" class="noprint"><div><nav><div><h2>Links</h2><ul><li><a href="../index.html">Docs Home</a></li><li><a href="index.html">Config Ref. Home</a></li><li><a href="https://wiki.apache.org/tomcat/FAQ">FAQ</a></li><li><a href="#comments_section">User Comments</a></li></ul></div><div><h2>Top Level Elements</h2><ul><li><a href="server.html">Server</a></li><li><a href="service.html">Service</a></li></ul></div><div><h2>Executors</h2><ul><li><a href="executor.html">Executor</a></li></ul></div><div><h2>Connectors</h2><ul><li><a href="http.html">HTTP</a></li><li><a href="ajp.html">AJP</a></li></ul></div><div><h2>Containers</h2><ul><li><a href="context.html">Context</a></li><li><a href="engine.html">Engine</a></li><li><a href="host.html">Host</a></li><li><a href="cluster.html">Cluster</a></li></ul></div><div><h2>Nested Components</h2><ul><li><a href="cookie-processor.html">CookieProcessor</a></li><li><a href="credentialhandler.html">CredentialHandler</a></li><li><a href="globalresources.html">Global Resources</a></li><li><a href="jar-scanner.html">JarScanner</a></li><li><a href="jar-scan-filter.html">JarScanFilter</a></li><li><a href="listeners.html">Listeners</a></li><li><a href="loader.html">Loader</a></li><li><a href="manager.html">Manager</a></li><li><a href="realm.html">Realm</a></li><li><a href="resources.html">Resources</a></li><li><a href="sessionidgenerator.html">SessionIdGenerator</a></li><li><a href="valve.html">Valve</a></li></ul></div><div><h2>Cluster Elements</h2><ul><li><a href="cluster.html">Cluster</a></li><li><a href="cluster-manager.html">Manager</a></li><li><a href="cluster-channel.html">Channel</a></li><li><a href="cluster-membership.html">Channel/Membership</a></li><li><a href="cluster-sender.html">Channel/Sender</a></li><li><a href="cluster-receiver.html">Channel/Receiver</a></li><li><a href="cluster-interceptor.html">Channel/Interceptor</a></li><li><a href="cluster-valve.html">Valve</a></li><li><a href="cluster-deployer.html">Deployer</a></li><li><a href="cluster-listener.html">ClusterListener</a></li></ul></div><div><h2>web.xml</h2><ul><li><a href="filter.html">Filter</a></li></ul></div><div><h2>Other</h2><ul><li><a href="systemprops.html">System properties</a></li></ul></div></nav></div></div><div id="mainRight"><div id="content"><h2>The Host Container</h2><h3 id="Table_of_Contents">Table of Contents</h3><div class="text">
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<ul><li><a href="#Introduction">Introduction</a></li><li><a href="#Attributes">Attributes</a><ol><li><a href="#Common_Attributes">Common Attributes</a></li><li><a href="#Standard_Implementation">Standard Implementation</a></li></ol></li><li><a href="#Nested_Components">Nested Components</a></li><li><a href="#Special_Features">Special Features</a><ol><li><a href="#Logging">Logging</a></li><li><a href="#Access_Logs">Access Logs</a></li><li><a href="#Automatic_Application_Deployment">Automatic Application Deployment</a></li><li><a href="#Host_Name_Aliases">Host Name Aliases</a></li><li><a href="#Lifecycle_Listeners">Lifecycle Listeners</a></li><li><a href="#Request_Filters">Request Filters</a></li><li><a href="#Single_Sign_On">Single Sign On</a></li><li><a href="#User_Web_Applications">User Web Applications</a></li></ol></li></ul>
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</div><h3 id="Introduction">Introduction</h3><div class="text">
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<p>The <strong>Host</strong> element represents a <em>virtual host</em>,
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which is an association of a network name for a server (such as
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"www.mycompany.com") with the particular server on which Tomcat is running.
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For clients to be able to connect to a Tomcat server using its network name,
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this name must be registered in the <em>Domain Name Service</em> (DNS) server
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that manages the Internet domain you belong to - contact your Network
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Administrator for more information.</p>
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<p>In many cases, System Administrators wish to associate more than
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one network name (such as <code>www.mycompany.com</code> and
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<code>company.com</code>) with the same virtual host and applications.
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This can be accomplished using the <a href="#Host_Name_Aliases">Host
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Name Aliases</a> feature discussed below.</p>
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<p>One or more <strong>Host</strong> elements are nested inside an
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<a href="engine.html">Engine</a> element. Inside the Host element, you
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can nest <a href="context.html">Context</a> elements for the web
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applications associated with this virtual host. Exactly one of the Hosts
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associated with each Engine MUST have a name matching the
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<code>defaultHost</code> attribute of that Engine.</p>
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<p>Clients normally use host names to identify the server they wish to connect
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to. This host name is also included in the HTTP request headers. Tomcat
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extracts the host name from the HTTP headers and looks for a
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<strong>Host</strong> with a matching name. If no match is found, the request
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is routed to the default host. The name of the default host does not have to
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match a DNS name (although it can) since any request where the DNS name does
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not match the name of a <strong>Host</strong> element will be routed to the
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default host.</p>
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<p><em>The description below uses the variable name $CATALINA_BASE to refer the
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base directory against which most relative paths are resolved. If you have
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not configured Tomcat for multiple instances by setting a CATALINA_BASE
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directory, then $CATALINA_BASE will be set to the value of $CATALINA_HOME,
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the directory into which you have installed Tomcat.</em></p>
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</div><h3 id="Attributes">Attributes</h3><div class="text">
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<div class="subsection"><h4 id="Common_Attributes">Common Attributes</h4><div class="text">
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<p>All implementations of <strong>Host</strong>
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support the following attributes:</p>
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<table class="defaultTable"><tr><th style="width: 15%;">
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Attribute
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</th><th style="width: 85%;">
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Description
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</th></tr><tr><td><strong><code class="attributeName">appBase</code></strong></td><td>
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<p>The <em>Application Base</em> directory for this virtual host.
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This is the pathname of a directory that may contain web applications
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to be deployed on this virtual host. You may specify an
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absolute pathname, or a pathname that is relative to the
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<code>$CATALINA_BASE</code> directory. See
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<a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information on automatic recognition and
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deployment of web applications. If not specified, the default of
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<code>webapps</code> will be used.</p>
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</td></tr><tr><td><code class="attributeName">xmlBase</code></td><td>
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<p>The <em>XML Base</em> directory for this virtual host.
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This is the pathname of a directory that may contain context XML
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descriptors to be deployed on this virtual host. You may specify an
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absolute pathname for this directory, or a pathname that is relative
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to the <code>$CATALINA_BASE</code> directory. See
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<a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information on automatic recognition and
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deployment of web applications. If not specified the default of
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<code>conf/<engine_name>/<host_name></code> will be used.</p>
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</td></tr><tr><td><code class="attributeName">createDirs</code></td><td>
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<p>If set to true, Tomcat will attempt to create the directories defined
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by the attributes <code>appBase</code> and <code>xmlBase</code> during
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the startup phase. The default value is <code>true</code>. If set to
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true, and directory creation fails, an error message will be printed out
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but will not halt the startup sequence.</p>
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</td></tr><tr><td><code class="attributeName">autoDeploy</code></td><td>
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<p>This flag value indicates if Tomcat should check periodically for new
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or updated web applications while Tomcat is running. If true, Tomcat
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periodically checks the <code>appBase</code> and <code>xmlBase</code>
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directories and deploys any new web applications or context XML
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descriptors found. Updated web applications or context XML descriptors
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will trigger a reload of the web application. The flag's value defaults
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to true. See
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<a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information.</p>
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</td></tr><tr><td><code class="attributeName">backgroundProcessorDelay</code></td><td>
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<p>This value represents the delay in seconds between the
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invocation of the backgroundProcess method on this host and
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its child containers, including all contexts.
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Child containers will not be invoked if their delay value is not
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negative (which would mean they are using their own processing
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thread). Setting this to a positive value will cause
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a thread to be spawn. After waiting the specified amount of time,
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the thread will invoke the backgroundProcess method on this host
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and all its child containers. A host will use background processing to
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perform live web application deployment related tasks. If not
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specified, the default value for this attribute is -1, which means
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the host will rely on the background processing thread of its parent
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engine.</p>
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</td></tr><tr><td><code class="attributeName">className</code></td><td>
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<p>Java class name of the implementation to use. This class must
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implement the <code>org.apache.catalina.Host</code> interface.
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If not specified, the standard value (defined below) will be used.</p>
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</td></tr><tr><td><code class="attributeName">deployIgnore</code></td><td>
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<p>A regular expression defining paths to ignore when
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<code>autoDeploy</code> and <code>deployOnStartup</code> are set. This
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allows you to keep your configuration in a version control system, for
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example, and not deploy a .svn or CVS folder that happens to be in the
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<code>appBase</code>.</p>
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<p>This regular expression is relative to <code>appBase</code>. It is
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also <em>anchored</em>, meaning the match is performed against the
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entire file/directory name. So, <code>foo</code> matches only a file or
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directory named <code>foo</code> but not <code>foo.war</code>,
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<code>foobar</code>, or <code>myfooapp</code>. To match anything with
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"foo", you could use <code>.*foo.*</code>.</p>
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<p>See <a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information.</p>
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</td></tr><tr><td><code class="attributeName">deployOnStartup</code></td><td>
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<p>This flag value indicates if web applications from this host should
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be automatically deployed when Tomcat starts. The flag's value defaults
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to true. See
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<a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information.</p>
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</td></tr><tr><td><code class="attributeName">failCtxIfServletStartFails</code></td><td>
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<p>Set to <code>true</code> to have each child contexts fail its startup
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if any of its servlet that has load-on-startup >=0 fails its own
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startup.</p>
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<p>Each child context may override this attribute.</p>
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<p>If not specified, the default value of <code>false</code> is
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used.</p>
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</td></tr><tr><td><strong><code class="attributeName">name</code></strong></td><td>
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<p>Usually the network name of this virtual host, as registered in your
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<em>Domain Name Service</em> server. Regardless of the case used to
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specify the host name, Tomcat will convert it to lower case internally.
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One of the Hosts nested within an <a href="engine.html">Engine</a> MUST
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have a name that matches the <code>defaultHost</code> setting for that
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Engine. See <a href="#Host_Name_Aliases">Host Name Aliases</a> for
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information on how to assign more than one network name to the same
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virtual host.</p>
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</td></tr><tr><td><code class="attributeName">startStopThreads</code></td><td>
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<p>The number of threads this <strong>Host</strong> will use to start
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child <a href="context.html">Context</a> elements in parallel. The same
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thread pool will be used to deploy new
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<a href="context.html">Context</a>s if automatic deployment is being
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used. The special value of 0 will result in the value of
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<code>Runtime.getRuntime().availableProcessors()</code> being used.
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Negative values will result in
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<code>Runtime.getRuntime().availableProcessors() + value</code> being
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used unless this is less than 1 in which case 1 thread will be used. If
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not specified, the default value of 1 will be used.</p>
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</td></tr><tr><td><code class="attributeName">undeployOldVersions</code></td><td>
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<p>This flag determines if Tomcat, as part of the auto deployment
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process, will check for old, unused versions of web applications
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deployed using parallel deployment and, if any are found, remove them.
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This flag only applies if <code>autoDeploy</code> is true. If not
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specified the default value of false will be used.</p>
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</td></tr></table>
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</div></div>
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<div class="subsection"><h4 id="Standard_Implementation">Standard Implementation</h4><div class="text">
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<p>The standard implementation of <strong>Host</strong> is
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<strong>org.apache.catalina.core.StandardHost</strong>.
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It supports the following additional attributes (in addition to the
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common attributes listed above):</p>
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<table class="defaultTable"><tr><th style="width: 15%;">
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Attribute
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</th><th style="width: 85%;">
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Description
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</th></tr><tr><td><code class="attributeName">copyXML</code></td><td>
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<p>Set to <code>true</code> if you want a context XML descriptor
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embedded inside the application (located at
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<code>/META-INF/context.xml</code>) to be copied to <code>xmlBase</code>
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when the application is deployed. On subsequent starts, the copied
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context XML descriptor will be used in preference to any context XML
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descriptor embedded inside the application even if the descriptor
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embedded inside the application is more recent. The flag's value
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defaults to <code>false</code>. Note if <strong>deployXML</strong>
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is <code>false</code>, this attribute will have no effect.</p>
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</td></tr><tr><td><code class="attributeName">deployXML</code></td><td>
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<p>Set to <code>false</code> if you want to disable parsing the context
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XML descriptor embedded inside the application (located at
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<code>/META-INF/context.xml</code>). Security conscious environments
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should set this to <code>false</code> to prevent applications from
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interacting with the container's configuration. The administrator will
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then be responsible for providing an external context configuration
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file, and putting it in the location defined by the
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<strong>xmlBase</strong> attribute. If this flag is <code>false</code>,
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a descriptor is located at <code>/META-INF/context.xml</code> and no
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descriptor is present in <strong>xmlBase</strong> then the context will
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fail to start in case the descriptor contains necessary configuration
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for secure deployment (such as a RemoteAddrValve) which should not be
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ignored. The flag's value defaults to <code>true</code> unless a
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security manager is enabled when the default is <code>false</code>.
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When running under a security manager this may be enabled on a per web
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application basis by granting the
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<code>org.apache.catalina.security.DeployXmlPermission</code> to the web
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application. The Manager and Host Manager applications are granted this
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permission by default so that they continue to work when running under a
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security manager.</p>
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</td></tr><tr><td><code class="attributeName">errorReportValveClass</code></td><td>
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<p>Java class name of the error reporting valve which will be used
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by this Host. The responsibility of this valve is to output error
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reports. Setting this property allows to customize the look of the
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error pages which will be generated by Tomcat. This class must
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implement the
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<code>org.apache.catalina.Valve</code> interface. If none is specified,
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the value <code>org.apache.catalina.valves.ErrorReportValve</code>
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will be used by default.</p>
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</td></tr><tr><td><code class="attributeName">unpackWARs</code></td><td>
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<p>Set to <code>true</code> if you want web applications that are
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placed in the <code>appBase</code> directory as web application
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archive (WAR) files to be unpacked into a corresponding disk directory
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structure, <code>false</code> to run such web applications directly
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from a WAR file. See
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<a href="#Automatic_Application_Deployment">Automatic Application
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Deployment</a> for more information.</p>
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<p>Note: If Tomcat expands the WAR file then it will add a file
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(<code>/META-INF/war-tracking</code>) to the unpacked directory
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structure which it uses to detect changes in the WAR file while Tomcat
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is not running. Any such change will trigger the deletion of the
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expanded directory and the deployment of the updated WAR file when
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Tomcat next starts.</p>
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<p>Note: Running with this option set to <code>false</code> will incur
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a performance penalty. To avoid a significant performance penalty, the
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web application should be configured such that class scanning for
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Servlet 3.0+ pluggability features is not required. Users may also wish
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to consider the <strong>ExtractingRoot</strong>
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<a href="resources.html">Resources</a> implementation.</p>
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</td></tr><tr><td><code class="attributeName">workDir</code></td><td>
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<p>Pathname to a scratch directory to be used by applications for
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this Host. Each application will have its own sub directory with
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temporary read-write use. Configuring a Context workDir will override
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use of the Host workDir configuration. This directory will be made
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visible to servlets in the web application by a servlet context
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attribute (of type <code>java.io.File</code>) named
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<code>javax.servlet.context.tempdir</code> as described in the
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Servlet Specification. If not specified, a suitable directory
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underneath <code>$CATALINA_BASE/work</code> will be provided.</p>
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</td></tr></table>
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</div></div>
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</div><h3 id="Nested_Components">Nested Components</h3><div class="text">
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<p>You can nest one or more <a href="context.html">Context</a> elements
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inside this <strong>Host</strong> element, each representing a different web
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application associated with this virtual host.</p>
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<p>You can nest at most one instance of the following utility components
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by nesting a corresponding element inside your <strong>Host</strong>
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element:</p>
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<ul>
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<li><a href="realm.html"><strong>Realm</strong></a> -
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Configure a realm that will allow its
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database of users, and their associated roles, to be shared across all
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<a href="context.html">Contexts</a> nested inside this Host (unless
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overridden by a <a href="realm.html">Realm</a> configuration
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at a lower level).</li>
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</ul>
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</div><h3 id="Special_Features">Special Features</h3><div class="text">
|
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|
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<div class="subsection"><h4 id="Logging">Logging</h4><div class="text">
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|
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<p>A host is associated with the
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<code>org.apache.catalina.core.ContainerBase.[engine_name].[host_name]</code>
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log category. Note that the brackets are part of the name,
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don't omit them.</p>
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</div></div>
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<div class="subsection"><h4 id="Access_Logs">Access Logs</h4><div class="text">
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|
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<p>When you run a web server, one of the output files normally generated
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is an <em>access log</em>, which generates one line of information for
|
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each request processed by the server, in a standard format. Catalina
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includes an optional <a href="valve.html">Valve</a> implementation that
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can create access logs in the same standard format created by web servers,
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|
or in any number of custom formats.</p>
|
|
|
|
<p>You can ask Catalina to create an access log for all requests
|
|
processed by an <a href="engine.html">Engine</a>,
|
|
<a href="host.html">Host</a>, or <a href="context.html">Context</a>
|
|
by nesting a <a href="valve.html">Valve</a> element like this:</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Valve className="org.apache.catalina.valves.AccessLogValve"
|
|
prefix="localhost_access_log" suffix=".txt"
|
|
pattern="common"/>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>See <a href="valve.html#Access_Logging">Access Logging Valves</a>
|
|
for more information on the configuration attributes that are
|
|
supported.</p>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="Automatic_Application_Deployment">Automatic Application Deployment</h4><div class="text">
|
|
|
|
<p>If you are using the standard <strong>Host</strong> implementation with
|
|
default settings then applications in the <em>appBase</em> or with context
|
|
files in the <em>configBase</em> are automatically deployed when Tomcat
|
|
starts (the <code>deployOnStartup</code> property defaults to
|
|
<code>true</code>) and reloaded or redeployed (as appropriate) when a change
|
|
is detected while Tomcat is running (the <code>autoDeploy</code> attribute
|
|
also defaults to <code>true</code>).</p>
|
|
|
|
<p><code>deployOnStartup</code> and <code>autoDeploy</code> trigger
|
|
execution of exactly the same code so the behaviour is very similar.
|
|
However, there is one key difference. When Tomcat starts it has no knowledge
|
|
of which files are the same, which have been changed and which are new. It
|
|
therefore treats all files as new. While Tomcat is running, it can
|
|
differentiate between unchanged, modified and new files. This leads to some
|
|
differences in behaviour between files being modified while Tomcat is
|
|
running and files being modified while Tomcat is stopped.</p>
|
|
|
|
<p>When you use automatic deployment, related files (a web application may
|
|
have a context.xml file, a WAR and a directory) that exist in the
|
|
<strong>Host</strong>'s <em>appBase</em> and/or <em>configBase</em>
|
|
must conform to the expected <a href="context.html#Naming">naming
|
|
convention</a>. In short, this means files for the same web application must
|
|
share the same <em>base name</em>.</p>
|
|
|
|
<p>The automatic deployment process identifies new and/or modified web
|
|
applications using the following search order:</p>
|
|
|
|
<ol>
|
|
<li>Web applications with a context.xml file located in the Host's
|
|
<em>configBase</em>.</li>
|
|
<li>Web applications with a WAR file located in the Host's
|
|
<em>appBase</em> that have not already been identified during the scan for
|
|
context.xml files.</li>
|
|
<li>Web applications with a directory located in the Host's
|
|
<em>appBase</em> that have not already been identified during the scans
|
|
for context.xml and/or WAR files.</li>
|
|
</ol>
|
|
|
|
<p>When <code>autoDeploy</code> is <code>true</code>, the automatic
|
|
deployment process will monitor the deployed web applications for changes.
|
|
Depending on exactly what changes, the web application will either be
|
|
re-deployed or reloaded. Re-deployment involves the creation of a new web
|
|
application and, if using the standard session manager, user sessions will
|
|
not be retained. Reloading uses the existing web application but re-parses
|
|
the web.xml and reloads any classes. If using the standard session manager,
|
|
user sessions will be persisted.</p>
|
|
|
|
<p>Users may add to the files that the automatic deployment process monitors
|
|
for reloading (i.e. any change to one of these files triggers a reload of
|
|
the web application) by adding a <em>WatchedResources</em> element to the
|
|
context.xml file. See the
|
|
<a href="context.html#Nested_Components">Context</a> documentation for
|
|
further details.</p>
|
|
|
|
<p>When using automatic deployment, the <code>docBase</code> defined by
|
|
an XML <a href="context.html">Context</a> file should be outside of the
|
|
<code>appBase</code> directory. If this is not the case, difficulties
|
|
may be experienced deploying the web application or the application may
|
|
be deployed twice. The <code>deployIgnore</code> attribute can be used
|
|
to avoid this situation.</p>
|
|
|
|
<p>Note that if you are defining contexts explicitly in server.xml, you
|
|
should probably turn off automatic application deployment or specify
|
|
<code>deployIgnore</code> carefully. Otherwise, the web applications
|
|
will each be deployed twice, and that may cause problems for the
|
|
applications.</p>
|
|
|
|
<p>There are many possible combinations of settings, new files, changed
|
|
files and deleted files. A separate page describes the
|
|
<a href="automatic-deployment.html">expected behaviour of the automatic
|
|
deployment process</a> in many of these scenarios.</p>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="Host_Name_Aliases">Host Name Aliases</h4><div class="text">
|
|
|
|
<p>In many server environments, Network Administrators have configured
|
|
more than one network name (in the <em>Domain Name Service</em> (DNS)
|
|
server), that resolve to the IP address of the same server. Normally,
|
|
each such network name would be configured as a separate
|
|
<strong>Host</strong> element in <code>conf/server.xml</code>, each
|
|
with its own set of web applications.</p>
|
|
|
|
<p>However, in some circumstances, it is desirable that two or more
|
|
network names should resolve to the <strong>same</strong> virtual host,
|
|
running the same set of applications. A common use case for this
|
|
scenario is a corporate web site, where it is desirable that users
|
|
be able to utilize either <code>www.mycompany.com</code> or
|
|
<code>company.com</code> to access exactly the same content and
|
|
applications.</p>
|
|
|
|
<p>This is accomplished by utilizing one or more <strong>Alias</strong>
|
|
elements nested inside your <strong>Host</strong> element. For
|
|
example:</p>
|
|
<div class="codeBox"><pre><code><Host name="www.mycompany.com" ...>
|
|
...
|
|
<Alias>mycompany.com</Alias>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>In order for this strategy to be effective, all of the network names
|
|
involved must be registered in your DNS server to resolve to the
|
|
same computer that is running this instance of Catalina.</p>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="Lifecycle_Listeners">Lifecycle Listeners</h4><div class="text">
|
|
|
|
<p>If you have implemented a Java object that needs to know when this
|
|
<strong>Host</strong> is started or stopped, you can declare it by
|
|
nesting a <strong>Listener</strong> element inside this element. The
|
|
class name you specify must implement the
|
|
<code>org.apache.catalina.LifecycleListener</code> interface, and
|
|
it will be notified about the occurrence of the corresponding
|
|
lifecycle events. Configuration of such a listener looks like this:</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Listener className="com.mycompany.mypackage.MyListener" ... >
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>Note that a Listener can have any number of additional properties
|
|
that may be configured from this element. Attribute names are matched
|
|
to corresponding JavaBean property names using the standard property
|
|
method naming patterns.</p>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="Request_Filters">Request Filters</h4><div class="text">
|
|
|
|
<p>You can ask Catalina to check the IP address, or host name, on every
|
|
incoming request directed to the surrounding
|
|
<a href="engine.html">Engine</a>, <a href="host.html">Host</a>, or
|
|
<a href="context.html">Context</a> element. The remote address or name
|
|
will be checked against configured "accept" and/or "deny"
|
|
filters, which are defined using <code>java.util.regex</code> Regular
|
|
Expression syntax. Requests that come from locations that are
|
|
not accepted will be rejected with an HTTP "Forbidden" error.
|
|
Example filter declarations:</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Valve className="org.apache.catalina.valves.RemoteHostValve"
|
|
allow=".*\.mycompany\.com|www\.yourcompany\.com"/>
|
|
<Valve className="org.apache.catalina.valves.RemoteAddrValve"
|
|
deny="192\.168\.1\.\d+"/>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>See <a href="valve.html#Remote_Address_Filter">Remote Address Filter</a>
|
|
and <a href="valve.html#Remote_Host_Filter">Remote Host Filter</a> for
|
|
more information about the configuration options that are supported.</p>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="Single_Sign_On">Single Sign On</h4><div class="text">
|
|
|
|
<p>In many environments, but particularly in portal environments, it
|
|
is desirable to have a user challenged to authenticate themselves only
|
|
once over a set of web applications deployed on a particular virtual
|
|
host. This can be accomplished by nesting an element like this inside
|
|
the Host element for this virtual host:</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Valve className="org.apache.catalina.authenticator.SingleSignOn"/>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>The Single Sign On facility operates according to the following rules:
|
|
</p>
|
|
<ul>
|
|
<li>All web applications configured for this virtual host must share the
|
|
same <a href="realm.html">Realm</a>. In practice, that means you can
|
|
nest the Realm element inside this Host element (or the surrounding
|
|
<a href="engine.html">Engine</a> element), but not inside a
|
|
<a href="context.html">Context</a> element for one of the involved
|
|
web applications.</li>
|
|
<li>As long as the user accesses only unprotected resources in any of the
|
|
web applications on this virtual host, they will not be challenged
|
|
to authenticate themselves.</li>
|
|
<li>As soon as the user accesses a protected resource in
|
|
<strong>any</strong> web application associated with this virtual
|
|
host, the user will be challenged to authenticate himself or herself,
|
|
using the login method defined for the web application currently
|
|
being accessed.</li>
|
|
<li>Once authenticated, the roles associated with this user will be
|
|
utilized for access control decisions across <strong>all</strong>
|
|
of the associated web applications, without challenging the user
|
|
to authenticate themselves to each application individually.</li>
|
|
<li>As soon as the user logs out of one web application (for example,
|
|
by invalidating the corresponding session if form
|
|
based login is used), the user's sessions in <strong>all</strong>
|
|
web applications will be invalidated. Any subsequent attempt to
|
|
access a protected resource in any application will require the
|
|
user to authenticate himself or herself again.</li>
|
|
<li>The Single Sign On feature utilizes HTTP cookies to transmit a token
|
|
that associates each request with the saved user identity, so it can
|
|
only be utilized in client environments that support cookies.</li>
|
|
</ul>
|
|
|
|
</div></div>
|
|
|
|
|
|
<div class="subsection"><h4 id="User_Web_Applications">User Web Applications</h4><div class="text">
|
|
|
|
<p>Many web servers can automatically map a request URI starting with
|
|
a tilde character ("~") and a username to a directory (commonly named
|
|
<code>public_html</code>) in that user's home directory on the server.
|
|
You can accomplish the same thing in Catalina by using a special
|
|
<strong>Listener</strong> element like this (on a Unix system that
|
|
uses the <code>/etc/passwd</code> file to identify valid users):</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Listener className="org.apache.catalina.startup.UserConfig"
|
|
directoryName="public_html"
|
|
userClass="org.apache.catalina.startup.PasswdUserDatabase"/>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>On a server where <code>/etc/passwd</code> is not in use, you can
|
|
request Catalina to consider all directories found in a specified base
|
|
directory (such as <code>c:\Homes</code> in this example) to be
|
|
considered "user home" directories for the purposes of this directive:</p>
|
|
|
|
<div class="codeBox"><pre><code><Host name="localhost" ...>
|
|
...
|
|
<Listener className="org.apache.catalina.startup.UserConfig"
|
|
directoryName="public_html"
|
|
homeBase="c:\Homes"
|
|
userClass="org.apache.catalina.startup.HomesUserDatabase"/>
|
|
...
|
|
</Host></code></pre></div>
|
|
|
|
<p>If a user home directory has been set up for a user named
|
|
<code>craigmcc</code>, then its contents will be visible from a
|
|
client browser by making a request to a URL like:</p>
|
|
|
|
<div class="codeBox"><pre><code>http://www.mycompany.com:8080/~craigmcc</code></pre></div>
|
|
|
|
<p>Successful use of this feature requires recognition of the following
|
|
considerations:</p>
|
|
<ul>
|
|
<li>Each user web application will be deployed with characteristics
|
|
established by the global and host level default context settings.</li>
|
|
<li>It is legal to include more than one instance of this Listener
|
|
element. This would only be useful, however, in circumstances
|
|
where you wanted to configure more than one "homeBase" directory.</li>
|
|
<li>The operating system username under which Catalina is executed
|
|
MUST have read access to each user's web application directory,
|
|
and all of its contents.</li>
|
|
</ul>
|
|
|
|
</div></div>
|
|
|
|
|
|
</div><div class="noprint"><h3 id="comments_section">
|
|
Comments
|
|
</h3><div class="text"><p class="notice"><strong>Notice: </strong>This comments section collects your suggestions
|
|
on improving documentation for Apache Tomcat.<br><br>
|
|
If you have trouble and need help, read
|
|
<a href="https://tomcat.apache.org/findhelp.html">Find Help</a> page
|
|
and ask your question on the tomcat-users
|
|
<a href="https://tomcat.apache.org/lists.html">mailing list</a>.
|
|
Do not ask such questions here. This is not a Q&A section.<br><br>
|
|
The Apache Comments System is explained <a href="../comments.html">here</a>.
|
|
Comments may be removed by our moderators if they are either
|
|
implemented or considered invalid/off-topic.
|
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</p><div id="comments_thread"></div></div></div></div></div></div></div><footer><div id="footer">
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